Sprint TP2 phone keypad icon?

[Chick3n]

Hi. Maybe this is a silly question for you guys, but I'm a new TP2 user and I can't find in the user manual what does it mean this icon/ symbol (looked like an "aiming crossfire") that appears on the top right of my phone keypad. Before it was like this at the attached image, but now it's crossed with a /...
I only find out that if I press it with the stylus it makes a sound that increases with every touch...

edit: did a soft reset after installing some cabs and the symbol is appearing exactly like in the attached image, without being crossed with the / like it was.